Wax compositions containing an ethylene-vinyl acetate copolymer an organic acid and a polyvinyl alkyl ether

ABSTRACT

THIS INVENTION RELATES TO WAX COMPOSITIONS CONTAINING A WAX, AN ETHYLENE-VINYL ACETATE COPOLYMER, AN ACID COMPONENT AND A POLYVINYL ALKYL ETHER. MOST PREFERABLY THE POLYVINYL ALKYL ETHER IS EITHER METHYL ETHER OR POLYVINYL ISOBUTYL ETHER. THESE COMPOSITIONS HAVE HIGHLY IMPROVED RESISTANCE TO STRESS CRACKING AND IMPROVED SEAL STRENGTH. THEY CAN BE UTILIZED AS HOT MELT COATINGS FOR ITEMS SUCH AS PAPERBOARD AND CORRUGATED BOARD FOR USE IN THE PACKAGING INDUSTRY AND PARTICULARLY AS PRESSURE SENSITIVE ADHESIVE COATINGS.

-"United States Patent O 3,660,333 WAX COMPOSITIONS CONTAINING AN ETHYL-ENE-VINYL ACETATE COPOLYMER, AN R- GANIC ACID AND A POLYVINYL ALKYLETHER Charles J. Kramer, Brookhaven, Pa., assignor to Atlantic RichfieldCompany, New York, N.Y. No Drawing. Filed July 22, 1969, Ser. No.843,787 lint. Cl. (309d 3/44 US. Cl. 260-43 H 14 Claims ABSTRACT OF THEDISCLOSURE This invention relates to Wax compositions containing a wax,an ethylene-vinyl acetate copolymer, an acid component and a polyvinylalkyl ether. Most preferably the polyvinyl alkyl ether is eitherpolyvinyl methyl ether or polyvinyl isobutyl ether. These compositionshave highly improved resistance to stress cracking and improved sealstrength. They can be utilized as hot melt coatings for items such aspaperboard and corrugated board for use in the packaging industry andparticularly as pressure sensitive adhesive coatings.

BACKGROUND OF INVENTION In United States application Ser. No. 457,218,now abandoned, filed May 19, 1965 in the name of Charles J. Kremer thereis disclosed improved wax compositions which contain wax, anethylene/vinyl acetate copolymer (EVA) and an acid. These compositionshave improved physical properties such as tensile strength, elongation,break energy, flex strength and seal strength. In United Statesapplication Ser. No. 557,901 (now US. Patent No.

3,417,040) filed June 16, 1966 in the name of Charles J. Kremer there isdisclosed an improvement in this basic wax system which comprisesutilizing as the acid a component which contains both a liquid and anacid. These compositions have properties which are even superior to thebasic wax/ acid system.

While these wax/acid compositions have many improved physicalproperties, no improvement was reported for their resistance to stresscracking. As used throughout the specification and claims resistance tostress cracking means the ability of a sample to resist cracking atpoints of surface stress in the material. This property is extremelyimportant in case of molded and extruded containers and in coated boardstock particularly when the stock is used by the packaging industry forfolded cartons. In molded or extruded containers and in folded cartonsthe stress is pronounced above the edges and scores. Stress failure isaccelerated by surface-active liquids such as soap solutions, fruitjuices, oils and fish and poultry body fluids. In packaging applicationswhich come in contact with these liquids during shipping, the stresscracking of the coated board permits them to penetrate into the board.

SUMMARY OF INVENTION It has now been discovered that if a polyvinylalkyl ether is utilized in the above described wax/EVA/acid system,tremendous improvements are obtained in the stress cracking resistanceof the composition and in its sealing properties.

Therefore, it is an object of this invention to provide Wax compositionswhich have improved resistance to stress cracking and seal strength.

In general the compositions of this invention comprise in parts byweight (A) 100 parts of a wax having a melting point of greater than 120F.

(B) from 5 to 150 parts of an ethylene-vinyl acetate copolymer having apolymerized vinyl acetate content ranging from 5 to 35 weight percentand a melt index ranging from 0.1 to 1000.

(C) from 1 to 30 parts of a polyvinyl alkyl ether having an averagemolecule weight ranging from 1,000 to 15,000.

(D) a wax-compatible, non-corrosive carborylic acid in an amountsufficient to impart to the composition a total acid number ranging from5 to 200, said acid itself having an acid number in excess of 20.

The wax component utilized in the composition of this invention can beof mineral, vegetable, animal or synthetic origin or mixtures thereof.The waxes must have a melting point greater than 120 F. Exemplarymineral origin waxes are the petroleum waxes, ozocerite and montan wax,etc. The petroleum and ozocerite waxes are comprised essentially ofparaffinic hydrocarbons, whereas the montan wax is comprised essentiallyof high molecular weight esters, with traces of alcohols and acid alsopresent. Examples of vegetable origin waxes are carnauba, candelilla,Japan waxes and the like. Animal Waxes suitable for use in the practiceof this invention are beeswax, Chinese wax, insect wax and similarwaxes. The main constituent of vegetable and animal origin waxes arehigh molecular weight esters and saturated hydrocarbons with smalleramounts of higher molecular weight alcohols and acids also beingpresent. Exemplary synthetic waxe are those produced by theesterification with polyhydric alcohols, the hydrogenation of vegetableoils and those made by the Fischer-Tropsch Synthesis etc.

As noted above, certain waxes are composed of mixtures of chemicalcompounds which include minor amounts of acids. Generally, however,these waxes do not have an acid number in excess of 20. It is thereforenecessary that the acid component be added in order to impart theminimum required acid number to the composition.

The use of petroleum waxes represents a preferred embodiment of thisinvention. These waxes include parafiin waxes which have a melting pointfrom 120 F. to 200 F. and the micro-crystalline waxes having a meltingpoint from 140 F. to 210 F. These waxes may be fully refined and thuscontain very small amounts of hydrocarbon oils or they may besemi-refined (slack waxes) and have hydrocarbon oil contents of up toabout 15 percent.

The most preferred compositions of this invention utilize a Waxcomponent containing either percent by weight microcrystalline wax orfrom 20 to 80 percent by weight of a paraflin wax having a melting pointranging from F. to 180 F. and from 80 to 20 percent of microcrystallinewax having a melting point ranging from F. to 200 F. These waxcomponents provide compositions which may be utilized in hightemperature applications. Increasing the concentration ofmicrocrystalline wax will impart a higher maximum use temperature andimprove the ultimate physical strength and performance while decreasingdimensional stability. With respect to parafiin waxes as a class the useof a non-normal parafiin wax imparts higher physical strength than thenormal base parafiin waxes.

The use of an ethylene-vinyl acetate copolymer (EVA) is critical to thepractice of this invention. This EVA copolymer should have a polymerizedvinyl acetate content ranging from 5 weight percent to about 35 weightpercent and a melt index ranging from 0.1 to about 1000 (ASTMD-1238-62). The preferred EVA copolymers are those having a polymerizedvinyl acetate content ranging from 15 weight percent to 35 weightpercent and a melt index ranging from about 0.1 to about 150. The mostpreferred EVA copolymers contain from 26-29 percent polymerized vinylacetate and have melt indices ranging from 0.1 to 25.

The concentration of EVA copolymer should be the minimum amountnecessary to impart the desired physical properties to the composition.Concentrations ranging from about to about 150 parts by Weight per 100parts of wax are operable. Preferably, the concentration of copolymerranges from about 5 to about 100 parts per 100 parts of wax. Mostpreferably it ranges from to 35 parts per 100 parts wax.

The third component which is critical to the practice of this inventionis a polyvinyl ether which is a liquid or semi-solid at 70 F. Thesepolyvinyl ethers have the following structural formula:

wherein R is an alkyl radical containing from 1 to 4 carbon atoms and nis an integer which defines the molecular weight of the polymer bydesignating the chain length. Specifically, under the above formula thepolyvinyl ethers can be methyl, ethyl, propyl, butyl or isobutyl ethers.Most preferably, the polyvinyl ether is either the methyl or theisobutyl ether. These polymers have average molecular weights rangingfrom about 1,000 to about 15,000 and preferably range from about 3,000to about 8,000. With respect to the unit structure, when R is methyl themolecular weight of the repeating unit is 58. When R is butyl themolecular weight of the structure is 100. Therefore, it broadly canrange from about 10 to about 260. In the preferred molecular weights itranges from about 30 to 140. These polyethers can be prepared by any ofthe art-recognized polymerizations such as those utilized in U.S. PatentNo. 2,104,000 and 2,061,934.

These polyvinyl ethers are incorporated into the wax compositions inamounts ranging from about 1 to about weight percent. Based on 100 partswax this loading corresponds from 1 to about 30 parts by Weightpolyvinyl ether. Most preferably, the polyvinyl ether is present in anamount ranging from about 5 to about 15 parts by weight per 100 parts byweight wax.

The fourth ingredient which is critical to the practice of thisinvention is the acid component. In general, any carboxylic acid whichis wax-compatible, non-corrosive and has an acid number in excess of canbe utilized in the compositions of this invention. It should beunderstood that a mixture of carboxylic acids can also be used in thecompositions of the present invention. The carboxylic acid must not becorrosive to the extent that it will attack the metal parts of equipmentor containers. In general, the lower molecular weight carboxylic acidssuch as, for example, formic, acetic, propionic, benzoic acids and thelike are very corrosive and in addition are generally incompatible withwax.

The carboxylic acid preferably should have an acid number in excess ofabout although acids with a lower acid number, i.e., about 20, can beused. Materials with a lower acid number, i.e., those of highermolecular weight are not desirable because they increase the viscosityof the molten composition without imparting corresponding or comparableincreases in the desired properties. Acid number is used herein as it isnormally understood by those skilled in the art, i.e., it is the numberof milligrams of alcoholic potassium hydroxide required to neutralize 1gram of the substance being tested in the presence of methyl orange. Anyaliphatic, alicyclic, or aromatic acid having one or more carboxylgroups may be used in the compositions of this invention provided,however, that such acids are wax-compatible, non-corrosive and have anacid number in excess of about 20. The aliphatic carboxylic acids can besaturated or unsaturated. Exemplary saturated aliphatic carboxylic acidsare nonanoic acid, lauric acid, tetradecanoic acid, pentacosanoic acid,natural occurring acids such as for example coconut fatty acid andtallow fatty acid, sebacic acid, 2- butyl-2-ethyl glutaric acid, and2-propyl-1,2,4-pentane tricarboxylic acid. Exemplary unsaturatedaliphatic carboxylic acids are oleic acid, linoleic acid, linolenicacid, and 5- octene-3,3,6-tricarboxylic acid. The alicyclic carboxylicacid may be saturated or unsaturated. Exemplary saturated alicycliccarboxylic acids are the naphthenic acids (cycloparafiinic acids),including those which have one or more alkyl side chains of varyinglength such as cyclohexane pelargonic acid. Exemplary unsaturatedalicyclic carboxylic acids are abietic acid and acids obtained bydimerizing or trimerizing higher molecular weight unsaturated fattyacids such as oleic or linoleic acid. Aromatic acids such as naphthoic,anthroic, alkyl substituted phthalic acid, and alkyl substitutednaphthalic acid may also be used in the practice of this invention.

Carboxylic acids that contain functional groups other than thecarboxylic group such as aldehyde, keto or hydroxyl groups can also beused in the compositions of this invention provided, however, that thefunctional group does not hinder the carboxyl moiety. Consequently,acids such as 12-hydroxy-stearic acid and oxidized petroleum waxeshaving an acid number in excess of about 20 can be also utilized in thecompositions of this invention. Acids containing small proportions ofother elements such as nitrogen, sulfur, oxygen, phosphorous etc. canalso be utilized provided the additional elements do not hinder thecarboxyl moiety. Examples of various acids which can be utilized are setforth in U.S. application Ser. No. 457,- 218 previously referred to andU.S. Patent No. 3,417,040 which are hereby incorporated by referenceinto this specification.

A preferred carboxylic acid is abietic acid, a source of which is woodrosin which contains more or less abietic acid depending on how it ischemically modified. Thus the products of wood rosin which have beensubjected to such chemical treatments as isomerization, air oxidation,hydrogenation, disproportionation, or dimerization are also suitable asthe carboxylic acid component. By subjecting the wood rosin to any ofthe above treatments, the relative amounts of the acids which comprisethe wood rosin are changed and consequently, the properties of the woodrosin may be varied to obtain the particularly desired properties. Forinstance, by oxidizing the wood rosin, it is possible to obtain aproduct with an increased softening point. Hydrogenation of the woodrosin results in a product with improved color stability. By submittingthe wood rosin to disproportionation, a product with improved oxidationresistance is obtained. Dimerization of the wood rosin yields a productof higher softening point. The methods of modifying wood rosin by anyone of the above chemical operations are Well-known to those skilled inthe art and the products obtained therefrom are available commercially.

As set forth in United States Patent No. 3,417,040 superior propertiesresults from the use of an acid component which contains both an acidand a liquid. This can be accomplished by either using a liquid acid orby using a solid acid (such as rosin) in combination with a liquid acidor non-acid. This combination should contain at least 35 weight percentof an organic acid having an acid number greater than 20. Secondly, itshould contain at least 5 weight percent of an organic liquid. Both theorganic acid and the organic liquid should have a boiling point greaterthan 300 F. at 7 mm. of mercury and both should be compatible with thewax, ethylene-vinyl acetate copolymer and polyvinyl ether at thetemperature at which the hot melt coating is being applied. Mostpreferably, the organic acid has an acid number in excess of 30 and ispresent in the acid component in an amount in excess of 50 weightpercent. Preferably, the organic liquid is present in the acid componentin an amount in excess of 20 weight percent.

While the preferred acid component must contain both an acid and aliquid, both of these requirements can be satisfied by utilizing anorganic carboxylic acid Which is also a liquid at 70 F. On the otherhand, both liquid organic acids and liquid organic non-acids can be usedin the same composition if desired. For example, liquid acids such asthe oligomers of fatty acids can be utilized alone or with a solidorganic acid or a liquid organic non-acid. If a liquid organiccarboxylic acid is used, it must have a melting point below 70 B, have aviscosity at 100 F. ranging from 500-10,000 SSU, have a molecular Weightranging from 400-2500 and have an acid number in excess of 20.Preferably, the acid has a viscosity at 100 F. ranging from SOD-2,000SSU and an average molecular Weight ranging from 400-800. Preferredliquid acids are the dimerized and trimerized fatty acids containingfrom 16-22 carbon atoms; for example, dimerized or trimerized oleic,arachidonic, sorbic or eicosenic acids. Most preferred are thedimerized, and trimerized eighteen carbon fatty acids, such as dimerizedor trimerized oleic or d linolenic acids.

Organic carboxylic acids which are not liquids at 70 F. can be utilizedif combined With at least weight percent of an organic liquid. Thissolid organic carboxylic acid must have an average molecular weightranging from 150 to 1500 and an acid number in excess of 20. Preferably,this acid has an average molecular weight ranging from 400-800 and has amelting point ranging from 120 200 F. A preferred solid organiccarboxylic acid is abietic acid which is commonly found in wood rosins.

The organic liquids which can be utilized in the practice of thisinvention must be liquids at 70 F. and have a boiling point greater than300 F. at 7 millimeters of mercury. As previously stated, the acidcomponent must contain at least 5 percent of a liquid organic acid or aliquid organic non-acid. If a liquid organic non-acid is utilized itmust be a hydrocarbon compound selected from the group consisting ofoils or a styrene, butene or propene polymer.

The oil which can be utilized as an organic liquid can be anyhydrocarbon oil having a viscosity at 100 F. ranging from 3003,000 SSU.Preferably, the oil has a viscosity at 100 F. ranging from 500-1500 SSU.The most preferred oil is a refined white oil.

The styrene polymers which can be utilized as the organic liquid in thisinvention must have a viscosity at 100 F. ranging from 800-100,000 SSUand an average molecular weight ranging from BOO-3,000. Preferably, theviscosity at 100 F. ranges from 800 to 3500 SSU and the averagemolecular weight ranges from 300-1500. These polymers can be prepared bypolymerizing various styrene monomers to produce low molecular weightpolymers. A mixture of styrene monomers can also be polymerized. Forexample, suitable polymers can be derived from styrene, alpha-methylstyrene or alkylated styrenes such as alkylated alpha-methyl styrene,alkylated alphamethyl paramethyl styrene, or alkylated para-methylstyrene, or mixtures thereof. A particularly suitable polymer of thistype is produced by the simultaneous alkylation and polymerization ofmonomeric styrene, alpha-methyl styrene, alpha-methyl para-methylstyrene, para-methyl styrene or a mixture of these monomers.

The liquid butene polymers which can be utilized as the organic liquidsin this invention must contain at least 90 percent by weight butene andhave a viscosity at 100 F. ranging from 1000 to 1,000,000 SSU and anaverage molecular weight ranging from 300-12,000. Copolymers containingbutene and up to 10 percent of another lower mono-olefin can also beutilized. Preferably the butene polymer is a homopolymer which has aviscosity at 100 F. ranging from 10,000 to 200,000 and an averagemolecular Weight ranging from 800-3000. Most preferably the averagemolecular weight ranges from 1600 to 2500. The most preferred butenepolymer is one prepared by the polymerization of butene-1 orisobutylene.

The propene polymer which can be utilized as an organic liquid in thisinvention has a viscosity at 100 F. ranging from 10,000-1,000,000 SSUand an average molecular Weight ranging from 800-3500. Preferably, thispolymer has a viscosity at 100 F. ranging from 20,000 to 50,000 SSU andan average molecular weight ranging from 1000 to 2000.

Preferred compositions can be prepared by utilizing as the acidcomponent a mixture of rosin acid and dimerized fatty acids or a mixtureof rosin acid and styrene polymer. For example, the acid component cancontain from 70 to percent by weight rosin acid and from 5 to 30 percentby weight of a dimer of 9,12-octadecadienoic acid or a styrenehomopolymer.

The acid component is incorporated into the composition of thisinvention in an amount sufficient to impart thereto an acid numberranging from 5-200. Most preferably, it is present in an amountsufiicient to impart an acid number ranging from 10-75. Theconcentration of acid component necessary to impart the required acidnumber will, of course, depend on the particular acid utilized, butgenerally it ranges from 10 to 150 parts by weight per parts wax.

Ingredients commonly added to wax or ethylene-vinyl acetate copolymerscan be incorporated into the compositions of this invention infunctional amounts without departing from the scope thereof. Examples ofthese ingredients include but are not limited to: heat and ultravioletstabilizers, inert fillers, secondary plasticizers, antiblocking agents,pigments and colorants, anti-oxidants, gloss stabilizers,viscosity-index improvers, solvents, antiscutf agents, etc.Specifically, ingredients such as the solid glycol esters of rosin acidscan be added to improve color, odor and heat stability. The preparationof the compositions of this invention is not critical to the practice ofit. For example, these compositions can be prepared by heating the waxto a temperature above its melting point, adding the ethylenevinylacetate copolymer, acid component, polyvinyl alkyl ether and otheradditives and agitating vigorously until a homogeneous hot melt isobtained. It has been found, however, that the acid componentfacilitates the dispersion of the polymers. Thefore, if this method isused it is preferable to incorporate the acid component into the meltedwax prior to the addition of the polymers. A specific method forpreparation is as follows: the waxes are melted together, anyanti-oxidants or heat stabilizers are added and the melt is then broughtto a temperature about 275 F. The acid component is heated to about 275F. and added to the hot melt. The ethylene-vinyl acetate copolymer andpolyvinyl alkyl ether are then added to the melt accompanied by vigorousstirring while maintaining the melt temperature above about 275 F. Afterall of the copolymer has been added the melt temperature is raised toabout 310 F. and agitated until the composition is homogeneous. Asdescribed in US. 3,417,040 the masterbatch system can be used. In thismethod the polymers are first mixed with the acid component by combiningthem at a temperature in excess of 250 F. When this blend is homogeneousit is added to the molten wax.

The following examples are given to illustrate specific embodiments ofthis invention and should not be construed as limitations to the scopeof the invention. All parts and percents are by weight.

Example I The blends of the table were prepared as follows. One half theamount of the wax and the acids were heated to 275 F. The EVA copolymerwas then added to this mixture and agitated until uniformly dispersed.The remaining portion of the wax was heated to 220 F. and the polyvinylether and polystyrene were added. The two mixtures were then combinedand agitated until homogeneous.

Parts by weight:

Petroleum wax (blend) 1 Inspections:

Viscosity, cp. at 250 F. 1, 371 1, 510 1, 462 1, 471 1, 217 Penetrationhardness at 110 F. 16 24 30 27 42 Tensile (p.s.i.) at:

Yield 420 335 305 307 257 315 210 190 201 160 Percent elongation 110 250280 307 261 Break energy, it. lbJcu.

in 47 50 59 67 40 Stress cracking (min.) 2 240+ 232 202 180 Seals(grams/inch): 1 to: Suliltc 189 Aluminum- 125 Glassinc 35 125 149 149176 Polypropylene 135 139 142 *150 Aluminum to:

Aluminum 80 210 224 233 240 Polypropylene 10 115 119 120 130 Glassineto:

Glassine 51 59 Aluminum 40 75 80 89 Acid No A 55 46 46 46 6 1 A blendcomprising 07 parts of a fully refined paraffin wax having a meltingpoint of 150 F. (ASTM D-87) and 33 parts of a microerystalline based waxhaving a melt point of 175 F. (ASTM D-127).

Z An ethylene-vinyl acetate copolyrner having a bound vinyl acetatecontent of 28 weight percent and a melt index of 1.5.

3 Gantrez M-094, a polyvinyl methyl ether having an average molecularweight 01 about 8,000.

4 Gantrez 13-201, a polyvinyl isobutyl ether having an average molecularweight of about 3,000.

5 Gantrez B-203, a polyvinyl isobutyl ether having an average molecularweight 01 about 6,000.

B A dimerized0,12octadecadienoic acid having a melting point of 35 R, anacid number of 190 and a viscosity at 100 F., of 1,000 SSU.

7 A viscous liquid polystyrene having an initial boiling point of 310 F.at 7 millimeters of mercury pressure, an average molecular weight of325-350, a specific gravity of about 1.03 and a viscosity at 100 F. atapproximately 1,500 SSU.

8 Disproportionated wood resin with a melting point of 181 F. (ring andball) acid number of 154, saponification of 189 and an average molecularweight of 450.

ASTM-D-1708-59T.

11 The stress cracking test utilized is a modification of ASTM D-1693-GOT. The procedure is as follows: Four test strips $6 x 2% were cut fromtwo cast slabs 0192 mils in thickness. The four test strips are thenaged at 73 F. :l:2 F. and 50 percent 315 percent relative humidity for24 hours. A detergent solution was then prepared containing 4% gallonsof distilled water, 5 ounces of dioctyl sodium sullosuccinate (AerosolOT-75 percent active) and 25 grams of acid black concentrated dye. Afteraging, the two ends of the test strip are brought together to form aloop and clamped in that position with a pinchcock. The loop with theclamp is immediately immersed in the detergent solution. A second stripis also immediately prepared and placed in the solution. The two samplesare then inspected initially at 30 second intervals and one minuteintervals thereafter for the appearance of stress cracks which appear onthe outermost edge of the loop. The time which is recorded in minutes isthat when the first sign of hairline cracks show in the sample. Afterthe first pair of samples fail, the procedure is repeated with thesecond pair of strips. The results of the four test strips are thenaveraged and reported as the stress cracking value.

TAPPI Test No. 042SU-64 (ASTH D-2005-) using TAPPI sulfite paper (5 lb.load per ream). A tear seal occurs when the two substrates cannot beseparated except by an actual tearing of one of the substrates,indicates a fiber pull seal which occurs when the separation causesfibers to be torn from one of the specimens.

13 Tear seal.

As demonstrated in the above table, compositions containing the fourcomponents of this invention have improved hardness, elongation, stresscracking and scaling properties over the control (Blend No. 1).

I claim:

1. A composition comprising in parts by weight:

(A) 100 parts of a wax having a melting point greater than 120 F.

(B) from 5 to 150 parts of an ethylene-vinyl acetate copolyrner having apolymerized vinyl acetate content ranging from 5 to 35 weight percentand a melt index ranging from 0.1 to 1000.

(C) from 1 to 30 parts of a polyvinyl alkyl ether having an averagemolecular weight ranging from about 1,000 to about 15,000.

(D) in an amount sufiicient to impart to the composition a total acidnumber ranging from 5 to 200, a

wax compatible, non-corrosive carboxylic acid said acid having an acidnumber in excess of about 20.

2. A composition according to claim 1 wherein the ethylene-vinyl acetatecopolyrner contains from 15 to 35 weight percent polymerized vinylacetate.

3. A composition according to claim 1 wherein the ethylene-vinyl acetatecopolyrner has a melt index ranging from 0.1 to 25.

4. A composition according to claim 1 wherein the concentration ofethylene-vinyl acetate copolyrner ranges from about 10 to about 35 partsper 100 parts of wax.

5. A composition according to claim 1 wherein the concentration ofpolyvinyl alkyl ether ranges from 5 to 15 parts per 100 parts by weightwax.

6. A composition according to claim 1 wherein the polyvinyl alkyl etherhas a molecular weight ranging from about 3,000 to about 8,000.

7. A composition according to claim 1 wherein the wax is a petroleumwax.

8. A composition according to claim 1 wherein the acid is a rosin acid.

9. A composition according to claim 1 wherein the polyvinyl alkyl otheris selected from the group consisting of polyvinyl methyl ether andpolyvinyl isobutyl other.

10. A composition according to claim 1 wherein the acid component hasboth liquid and acid properties said component containing at least 35percent by weight acid and at least 5 percent by weight liquid, allhaving boiling points greater than 300 F. at 7 millimeters of mercury,said acid being selected from the group consisting of (A) an organiccarboxylic acid which is a liquid at 70 F., has a viscosity at 100 F.ranging from 500 to 10,000 SSU, an average molecular weight ranging from400 to 2500, and an acid number in excess of 20,

(B) an organic carboxylic acid which has a melting point above 70 R, anaverage molecular weight ranging from 150 to 1500, and an acid number inexcess of 20, and

(C) Mixtures of (A) and (B) said liquids being selected from the groupconsisting of:

(A) an organic carboxylic acid which is a liquid at 70 F., has aviscosity at 100 F. ranging from 500 to 10,000 SSU, and averagemolecular weight ranging from 400 to 2500, and an acid number in excessof 20.

(B) a hydrocarbon which is a liquid at 70 F. selected from the groupconsisting of:

(1) an oil having a viscosity at 100 F. ranging from 300 to 3,000 SSU,

(2) a styrene polymer having a viscosity at 100 F. ranging from 800 to100,000 SSU and an average molecular weight ranging from 300 to 3,000,

(3) a butene polymer containing at least percent weight butene, having aviscosity at F. ranging from 1000 to 1,000,000 SSU and an averagemolecular weight ranging from 300 to 12,000.

(4) a propene polymer having a viscosity at 100 F. ranging from 10,000to 1,000,000 SSU and an average molecular weight ranging from 800 to3,500,

(C) mixtures of (A) and (B).

11. A composition according to claim 1 wherein the acid component of (D)is a mixture containing a liquid acid and rosin acid.

12. A composition according to claim 1 wherein the acid component of (D)is present in an amount sufficient to impart to the composition an acidnumber ranging from 10 to 75.

13. A composition according to claim 1 wherein:

(A) the wax component is a blend of parafiin wax and microcrystallinewaxes (B) the ethylene-vinyl acetate copolymer has a polymerized vinylacetate content ranging from to 35 percent by weight, a melt indexranging from 0.1 to and is present in an amount ranging from 10 toparts,

(C) the polyvinyl alkyl ether is selected from the group consisting ofpolyvinyl methyl ether and polyvinyl isobutyl ether and is present in anamount ranging from 5 to 15 parts,

(D) the acid component is present in an amount willcient to impart tothe composition an acid number ranging from 10-75 and is a mixturecomprising (1) from to percent by weight of rosin acids,

(2) .from 5 to 30 percent by weight of a dimer of 9,12-octadecadienoicacid.

14. An article of manufacture coated on at least one side thereof withthe composition of claim 1.

References Cited UNITED STATES PATENTS 3,330,792 7 1967 Gaylord260--28.5 3,409,498 11/1968 Suter et al. 161-252 3,417,040 12/ 1968Kremer 26027 10 DONALD E. CZAJA, Primary Examiner W. E. PARKER,Assistant Examiner US. Cl. X.R.

15 161-216, 249, 252; 26027 EV, 28.5 AV

